Neutralizer bar



Patented Jan. 12, 1932 UNITED "STATES PVATEVNT- OFFICE WILLIAM HENRY orPORTLAND, MAINE, Assmmn To cmiaannmq TRIC NEUTRALIZER column, orPORTLAND, A CORPORATION or MAINE lmummznn BAR Application filed December18, 1980. Serial No. 503,246.

This inventionv relatesto discharge bars for neutralizing staticelectricity, and particularly for neutralizing static electricity onmoving sheets of paper or fabric occurring in the process ofmanufacturing such sheets 1 or in printing thereon. As such it involves.certain improvements upon my prior Patents 940,431, granted November 16,1909 and 1,653,599,, granted December20, 1927 to which reference is heremadeas disclosing a discharge bar of the general type involved herein.

More specifically, my present invention is directed to the'removal ofcertain practical difficulties which have beennoted in the use of adischarge bar of this type. One characteristic difiiculty has beenthat'spark discharges sometimes occur inside the discharge bar betweenthe ends of the induction sleeves indicated at g in Patent 940,431 andM30 in 1,653,599 and the outside'ca'sing, thus reducing the efficiencyof the bar.

According to my present invention I overcome this objection by deeplycounter-sinking the sleeves in their insulating blocks so that the endsof the sleeves are surrounded by the enclosing ends of the blocks, thusavoiding anyvspark discharge from the ends of the induction sleevesradially towards the" sides of the outside casing.

. Another difiiculty with all previous discharge barsof this type hasbeen that in order to prevent admission of dirt or other foreign:

matter into the bar a greater uniformity and accuracy of fit of theinsulating blocks there in has been demanded than canbe secured in theprocess of manufacture of the blocks.

These blocks are made of porcelain, on ac count of the superiorinsulating qualities'of.

this material. but porcelain does not. lend itself to molding withsufiicient accuracy to atford that tightness of fit so necessary to exelude dirt or other foreign matter from the bar. r I

I overcome this difiiculty in my present invention by the provision ofresilient means,

as flat steel springs interposed between theoutside casing and theinsulating blocks and effective to press the blocks firmly against theblocks themselves becomes a factor, my present blocks being purposelyconfigured sub-' stantially to conform to the internal curvature of thecasing along spaced longitudinal lines of bearing at either side oftheslot in said casing, thus effectively sealing the slot against ingressof dirt or other foreign matter. The'compression springs are so mountedbetween the outside casing andthe blocks as to be securely anchoredagainst any tendency to work free from the blocks when the discharge baris assembled.

A- further difiiculty in all previous types of discharge bars hasconsisted in the mountries as many as fifty or more discharge points,

the matterot cleaning out each individual opening is a long and tedioustask involving as it does the'iritroduction of a rag brush, or othercleaning implement into each indivldual opening and thereaftertwlstingthe same so as to Wipe any accumulated dirt out of the opening.

I overcome this obj ection in my present in-' vention by providing eachinsulating block with a longitudinal groove extending from end to endthereof so that when all the blocks are assembled in the hearingacontinuous groove is afforded from end to end of the bar which groovecanbe quickly and completely cleaned by drawing a rag, brush or othercleaning implement from end to end of the bar instead of introducing therag into each individual opening and twisting the same therein as hasbeen heretofore necessary. With my improved construction the resilienceof the cone shaped discharge points permits. a vigorous wiping orbrushing 1Ct10I1Wltll out injury to the points and the groove withinwhich the points are located protects them laterally so that the edgesof the moving sheets of paper cannot catch and injure them as wouldoccur if the points were not protected by a. suitable enclosure ofinsulating material. In other words, the continuous groove in my presentconstruction affords even greater protection to the discharge pointsthan did the individual openings in my prior constructions whileenabling the discharge bar to be cleaned far more thoroughly and. withconsiderable less ellort and. time than was possible with suchcoristructions.

Other features of innn'ovelnent and advantage will be more particularlypointed out hereinafter.

As illustrative of the principles involved I show in the accompanyindrawings a form of discharge bar which I have found highly satisfactoryunder actual service conditions and Well adapted to the requirements ofmanufacture.

In the drawings Fig. 1 is an elevation of a discharge bar equipped inaccordance with my present invention, the outside casing being partlybroken away to disclose the internal constructimr Fig. 2 an enlargedfragmentary longitudinal section.

Fig. 3 is a cross section on the same scale as Fig. 2, the insulatingblock being shown, however, in end elevation. and

Fig. 4 is a perspective view (it one of my insulating blocks removed.

As in my said prior patents hereinbefore referred to, the discharge barconsists generally of an outside casing 1 of steel or other suitablematerial having a longitudinal slot 2 extending from end to end thereof.The casing 1 is mounted in the usual manner for the passage therethroughof charges of alternating current. For the purposes of this applicationI have simply indicated at 3 a lead adapted to be connected. with anysuit-- able source of high tension alternating current. The lead 3 iselectrically connected with a cable or the like 1 extending from end toend of the casing, said casing being grounded as at 5. The moving sheet01 fah-- ric, paper or other material is indicated at (i and thedischarge bar is mounted in such relation to said sheet as to controlthe electrostatic charges generated therein during the process ofmanufacturing or printing such sheets.

Assembled within the casing 1 is a plurality of insulating blocks 7. Thee blocks may be made of any suitable insulating mate rial but arepreferably made of porcelain. They are assembled in end to end abutmentWithin the casing 1 and each bloci: serves as a mounting for condenserin the form of a metallic sleeve 8 which is Fixed axially there in andalso carries one or more discharge points 9 of conical form havingenlarged.

. heads 10 disposed in electrical conducting relation to the sleeves 8interior of the block.

As contemplated herein the sleeves 8 are deeply counter-sunk in theblocks 7 so that the ends 8' of the sleeves terminate inside of theenclosing ends 7 of the blocks, thus to avoid any danger of sparkdischarges radially across from the ends of the sleeve to the insidesurface of the metal casing 1.

i In :wcon'iplishhig this result the blocks 7 are molded with an axialopening 7 the ends of which are ei'ilarged as at 7 so that the effectthat of a bore and a counter-bore. Adopting this terminology the here isthe opening 7 and the counter-bores are the enlargements 7 at the endsof the bore 7 V The sleeve 8 fits tightly within the bore 7 the ends ofthe sleeve being headed over if desired to retain the sleeve in place,as best shown in Fig. 2 and as indicated by the reference character 8.

The shape of each block is such as to fit reasonably tightly within thecasing 1 when entered endwise therein, being rounded as at 11. 12 and 13in Fig. 3 to conform generally to the curvature of the casing.

In order to insure that tightness of fit necessary to exclude theentrance of dirt or other foreign matter into the bar I provide meansfor positively pressing the individual blocks into firm contact with thecasing at the bearing surfaces 12 and 13. Such means may take the formof a series of bowed steel springs 14 each of a length to fit snuglywithin a cavity 15 formed in the surface 11 of the block. The cavity 15prevents in the spring 14 from accidentally disengaging from the blockwhen the block is assembled in the easi ng. In such assembly the sprinitself bears against the inside surface of the casing 11 and iscompressed thereby and thus presses the block firmly against the casingat the hearing surfaces 12 and 13.

The discharge points 9 may be assembled in any desired manner. As hereshown each block is internally grooved as at 16. The groove 16 extendsfrom end to end of the block and opens into the opening 7 of the block.Between its ends. each groove is intersected at one or more points byopenings 17 within which the helical portions of the discharge pointsare mounted with the points themselves extending slightly beyond theoutermost surface of the block and the enlarged heads or bases 1.0 ofsaid points lodged in the groove 16 in contact with the sleeve 8.

In order to protect the discharge points against injury by the movingsheets of paper 6 and also to enable the block readily to be cleaned,that portion of the block which registers with the longitudinal slot 2of the casing 1 is grooved cxteriorly from end to end as indicated at18. The grooves 18 permit the blocks to be cleaned by wiping them fromend to end of the bar with a rag or other cleaning implement and theribs 19 left by said groove serve to'protect the discharge pointsagainst injury. 7

From the foregoing it is believed that the construct-ion and advantagesof-my present.

stallation and hence are to be regarded as within the spirit and scopeof my invention if within thelimits of the appended claims.

- What I therefore claim and desire to secure by Letters, Patent is: i

1'. A discharge bar of the class described comprising a casing, aninsulating unit mounted therein, and means independent of the casing andthe insulating unit and compressively confined therebetween for resili-.

entl ur in the insulatin unita ainst the a: a: r: a I

casing. V

2. A discharge bar of the class described comprising a casing, aninsulating unit mounted therein, and meansbetween the casing and theinsulating unit for resiliently urging the insulating unit against thecasing, the casing being curved and the insulating unit having bearingsurfaces substantially opposite said means conforming generally to thecurvature of the casing. a

3. A discharge bar of the class described comprising a. casing, aninsulating unit mounted therein, and a spring compressively confinedbetween the casing and the insulating unit for resiliently urging theinsulating unit against the casing.

4. A discharge bar of the class described comprising a casing, aninsulating unit mounted therein, and a spring compressively confinedbetween the casing and the insulating unit for resiliently urging theinsulating unitagainst the casing, the casing being curved and theinsulating unit having hearing surfaces substantially opposite saidspring conforming generally to the curvature of the casing. r

5. A discharge bar of the class described. comprising a casing.- aninsulating unit mounted therein and having a cavity, and a bowed springcompressively confined in the cavity of the insulating unit and betweenand the casing for resiliently urging the insulating un t against thecasing.

6. A discharge bar of the class described comprising a casing, aninsulating unitmounted therein and having a cavity, and a bowed springcompressively confined in the cavity of the insulating unit and betweenit and the casing for resiliently urging the in sulating unit againstthe'casing, the casing be ng curved and the insulating unit havingbearing surfaces substantially opposite said spring conforming generallyto the curvature of the casing.

T. In a discharge bar of the class described, a slotted casing, aplurality of insulating units assembled within said casing and havingdischarge points exposed through the slot thereof, each unit having alongitudinal groove from end to end thereof within which the dischargepoints are centered so as to be protected by the walls of said groovesand said grooves permitting the discharge points to be cleaned by'awiping action from end to end of the bar,.the surfaces of saidinsulating unit on either side of said groove bearing against the casinginteriorly thereof, and a spring confined between each insulating unitand the casing opposite said bearing surfaces .for resiliently urgingsaid units against the casing.

8. In a discharge bar of the class described, a casing, an insulatingunit mounted within said casing, said unit having an axial opening, theends of said opening being of greater diameter than the opening itself,and a sleeve mounted in said opening with its ends termi nating short ofthe enlarged ends of the opening so asto be protected by the overhangingend portions of the insulating unit against radial sparking to the sideof the casing.

9. In a discharge bar of the class described, a casing, an insulatingunit mounted within said casing, said unit having an axial opening, theends of said opening being of greater diameter than the opening itself,and a sleeve mounted in said opening with its ends terminating short ofthe enlarged ends of the openin so as to be protected by the overhangingend portions of the insulating unit against radial sparking to the sideof the casing, the ends of said sleeve being headed over into theenlarged ends ofsaid axial opening in order positively to retain thesleeve in position within said opening. 1

10. In a discharge bar of the class described, a casing, an insulatingunit mounted within said casing, said unit having an axial opening. theends of said opening being of greater diameter than the opening itself,and

a sleeve mounted in said opening with its ends terminating short of theenlarged ends 11. In a discharge bar of the class described, a casing,an insulating unit mounted within said casing, said unit having an axialopenin the ends of said opening being of greater diameter than theopening itself, and

position within said op ning, said al opening being intersected by alongiaal groove and said lon udinal groove bee-1g intersected by anopening for a discharge point, and a discharge point mounted in said 1.:named openin with its inner end lodged in arid hingitedinal groove andits end. exoosed beyond said insulating unit.

12. In a d charge er of the class de scribed, a sl casing. pluralit tinrting blocks :ssembled in one in end rela- 'thin said casinu. eachblock being eX grooved from o r to end and each end; adjacent said rooveha. ng bearing :uufi'aces correspondir in configuration to the generalconfiguration of the casing, a spring assembled upon each block and eXposed for compressive engagement by the casting whereby to resilientlypress each block against tne casing at said bearing surfaces 13. In adischarge bar of the class descri ed, a slotted c-asingr a plurality ofin- :ndating blocks assembled in end to end relat on wthin said casing,each block being 1;. iorly grooved from end to end and each blockadjacent said groove having bearing surfaces corresponding inconfiguration to the general configuration ot the casing, a springassembled upon each block and c1;- p -"(l for compressive engagement bythe g whereby to resiliently press each block against the casing at saidbearing surfaces, ta" blocks being formed with cavities to recive saidsprings.

14. In a discharge bar oil the class described, a slotted casing, aplurality of insulating blocks assembled in end to end relation withinsaid casing, each block being exteriorly grooved from end to end andeach block adjacent said groove having bearing surfaces corresponding inconfiguration to the general. configuration of the casing, a springass-:embled upon each block and ere posed for compr ssive engagement bythe casiir whereby to resiliently press each block against the casing atsaid bearing surfaces, 1- ch block having an axial opening t rniinatingin enlarged ends, a sleeve mounted in each opening with its endsterminating short of the ends of the block so as to be protected betweenoverhanging portions of the block against radial sparking to the insidesurface of the casing, and each block having one or more openingsdisposed transversely to said sleeves, and discharge points mounted insaid openings with their inner ends disposed adjacent said sleeves andtheir outer ends extending into said external grooves and protected bythe walls of said grooves.

15. In a discharge bar of the class described a slotted casing, apluralty of insulating blocks assembled in end to end rotation withinsaid casing, each block being or teriorly grooved from end to end and-,ach block having an axial opening terminating in enlarged ends, asleeve mounted in each opening with its ends terminating short of theends of the block so as to be protected between overhanging portions ofthe block against radial sparking to the inside surface of the casing,and each block having one or: more openings disposed transversely tosaid sleeves, and discharge point-s mounted in said openings with theirinner ends disposed adjacent said sleeves and their outer ends extendinginto said external grooves and protected by the walls of said grooves.

16. An insulating unit for use with the slot-ted easing of a dischargebar of the class described, consisting of a block of insulating materialassembled within said casing, said block having an axial opening theends of which are of greater diameter than the opcning itself and withinwhich opening a sleeve of less length than the length of the opening isadapted to be mounted so as to be protected by the overhanging endportions of said block against radial sparking to the side of thecasing, said block having a longitudinal groove extending from end toend thereof and registering with the slot of the casing, the walls ofsaid groove constituting a pro tectivc enclosure for a discharge pointwhich projects outwardly through said groove and slot of casing, and thegroove itself permittin the discharge point to be cleaned by ng actionfrom end to end the block.

17. An insulating unit for use with the slotted casing of a dischargebar of the class described, consisting of a block of insuhiting materialassembled within said casing, said block having an axial opening theends of which are of greater diameter than the o1 )ening itself: andwithin which opening a sleeve oi. less length than the length oil theopening is adapted to be mounted so as to be protected by theoverhanging end portions of said block a ainst radial sparking to theside ol the casin In testimony whereof I affix my signature.

lVILLIAM HENRY CILXPMAH.

